docs: def notify_badge_added_certified(sender, kind=''):
      '''
      Send an email when a `CERTIFIED` badge is added to an `Organization`
  
      Parameters
      ----------
      sender
          The object that emitted the event.
      kind: str
          The kind of `Badge` object awarded.
      '''
      if kind == CERTIFIED and isinstance(sender, Organization):
          recipients = [member.user for member in sender.members]
          subject = _(
              'Your organization "%(name)s" has been certified',
              name=sender.name
          )
          mail.send(
              subject,
              recipients,
              'badge_added_certified',
              organization=sender,
              badge=sender.get_badge(kind)
          )